Roebling's Delaware Aqueduct

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Delaware Aqueduct
Delaware Aqueduct post-restoration by the NPS
Carries	Motor vehicles
Crosses	Delaware River
Locale	Minisink Ford, New York to Lackawaxen, Pennsylvania.
Maintained by	National Park Service
Design	Suspension bridge
Total length	535 feet (175 m)
Opening date	1847
Maps and aerial photos

Roebling's Delaware Aqueduct is the oldest existing wire suspension bridge in the United States; it runs 535 feet (175 meters) from Minisink Ford, New York to Lackawaxen, Pennsylvania. It is also known as the Delaware Aqueduct, or Roebling Bridge. Begun in 1847 as one of four suspension aqueducts on the Delaware and Hudson Canal (D & H), it was designed by and built under the supervision of John A. Roebling, who would design the Brooklyn Bridge twenty years later. Portions of the D & H Canal, including the Delaware Aqueduct, were designated a National Historic Landmark in 1968. The Delaware Aqueduct is also designated a National Civil Engineering Landmark. The aqueduct was used as a vehicular bridge until 1979; it was restored by the National Park Service in 1985 and is now part of the Upper Delaware Scenic and Recreational River.

The Delaware and Hudson Canal and Gravity Railroad was a system of transportation between coal fields of northeastern Pennsylvania and markets on the Hudson River that operated from 1828 until 1898, with enlargements after the 1840s.

Two important local industries with conflicting needs brought about construction of Roebling's Delaware and Lackawaxen Aqueducts: canal traffic and timber rafting. Since the mid-1700s, timber from the Delaware valley had been floated down the Delaware to shipyards and industries in Trenton and Philadelphia. The D & H Canal operated a rope ferry crossing of the Delaware at Lackawaxen but it created a major bottleneck before the aqueduct was built, and there were numerous collisions with timber rafts headed downstream. In 1847, to alleviate both problems, the D & H Canal Company approved John Roebling's plan to "build the canal above the river."

Compared to conventional bridges, Roebling's suspension design allowed more room for ice floes and river traffic. An immediate success, the $41,750 Delaware Aqueduct and the $18,650 Lackawaxen Aqueduct (only the abutments remain) reduced canal travel time by one full day, saving thousands of dollars annually.

List of crossings of the Delaware River

	Delaware Aqueduct post-restoration by the NPS	Another post-restoration picture	A view down the center of the one lane bridge
The visible cables of the suspension bridge	Part of the bridge's foundation pointing upstream	Delaware Aqueduct before restoration. Notice the suspension cables, which are hidden in the restored aqueduct by the canal sides. (NPS photographs)